Nucleotides

• Nucleotide consists of pentose sugar, nitrogenous base and phosphate group
• Pentose sugar means it has 5 carbons
• Nucleoside consists of pentose sugar and nitrogenous base
• In nucleotide, pentose sugar and phosphate groups are polar and create a backbone when linked together (face out)
• In nucleotide, nitrogenous bases face in, because they create hydrogen bonds with each other
• Nucleotides join together by phosphodiester bond in 5' to 3' direction
• In nucleotides, nitrogenous bases are always attached to carbon number 1
• When we have DNA sequence written, top is in 5' to 3' direction and bottom is written in 3' to 5' direction
• Adenine can form 2 hydrogen bonds with Thymine
• Cytosine can form 3 hydrogen bonds with Guanine
• Pyrimidines are cytosine, uracil and thymine
• Purines are adenine and guanine
• This is structure of guanine

  
• This is a structure of adenine

  
• This is a structure of cytosine

  
• This is a structure of thymine

  
• This is a structure of uracil

  
• More energy is required to separate GC bond
• In RNA, carbon number 2 has OH group attached
• Picture number one has pentose sugar of DNA and picture number 2 has pentose sugar of RNA

  
• Melting temperature of nucleotide chain depends on the amount of guanine and cytosine in the chain
• This is a structure of ATP

  
• Phosphodiester bond between nucleotides is formed in dehydration reaction
• During phosphodiester bond formation, phosphate at 5C position joins OH at 3C position and H2O is produced
• Thymine has 3 functional groups (CH3, O and O)
• Cytosine has 2 functional groups (NH2, O)
• Uracil has 2 functional groups (O and O)
• Phosphodiester bond is covalent type of bond